Typically, a continuous casting process is a process of continuously pouring molten steel into a mold having a certain shape, continuously drawing semi-solidified molten steel in the mold towards the bottom side, and manufacturing a semi-finished product having various shapes such as a slab, a bloom, or a billet. The mold has cooling water circulated therein to semi-solidify the poured molten steel and make a certain form. In other words, the molten steel in a molten state is semi-solidified by a cooling action in the mold, non-solidified molten steel drawn from the mold is solidified by air mist in which air and cooling water sprayed from a slab cooling system are mixed to form a slab in a perfect solid state.
Primary cooling in the mold is the most important process for determining slab surface quality. In other words, the primary cooling depends on the molten steel flow in the mold. When a rapid flow or a bias flow occurs in the meniscus, a mold flux playing a role of lubricant and heat reserving is caused and accordingly defects occur on the slab.
Accordingly, once the flow of meniscus is measured, slab defects may be predicted. However, since meniscus maintains a high temperature state, it is very difficult to measure a flow thereof in real time. In addition, even though a technique for measuring the height of the meniscus using an eddy current level meter to control a uniform height of the molten steel in the mold is commercially available, since the height of only any one point is measured, it is not possible to measure the molten steel flow of the entire meniscus. In addition, since a mold flux is coated on the meniscus for reserving heat of the meniscus, naked eye observation using a camera or the like is not possible.
Of background interest is Korean patent laid-open publication No. 2001-0055792.
The present invention provides an apparatus and method for predicting slab quality capable of visualizing a meniscus flow to a user and predicting quality such as presence or not of slab defects using a pattern according to a meniscus flow type.
The present invention also provides an apparatus and method for predicting slab quality capable of measuring a meniscus flow in real time by preparing a plurality of meniscus height detecting units including temperature detecting means on the mold and detecting the height of the meniscus using the prepared meniscus height detecting unit.
The present invention also provides an apparatus and method for predicting slab quality capable of storing a meniscus flow pattern and quality of a slab produced accordingly as data, and predicting the slab quality according to the data stored according to the meniscus flow pattern, which is measured in real time through a plurality of meniscus position detecting units.